It's an extremely common phrase in the US, along with "Is the Pope Catholic?" Sometimes the two phrases are humorously mixed together.
replyI've never heard it mixed (not from US)...
reply"Is bear a Catholic?" doesn't seem very funny.
But a notion that everyone knows how Pope is regularly shitting in the woods absolutely is :)
We say "are bears Catholic?" when in more polite company and we can't get away with asking if the Pope shits in the woods :)
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